I only recently learned that Erin’s graphs aren’t always consistent
Thank you for pointing out Spinorama’s are
Though if Robert-Hifi hadn’t posted, I would not have known Monsieur Pierre is Mr Spinorama.
Spinorama has a very wide range of gear, including some very $$$ … is Pierre responsible for all the data at Spinorama?
It is a database of measurements, collected from a variety of sources. The source is listed for each speaker.